High voltage devices, for example, lateral double-diffused metal oxide semiconductors (LDMOS), have been widely used for high voltage applications. Indicators of the performance of high voltage devices may include their switching speeds and reliability. The switching speeds of the high voltage devices may be affected by factors, such as their drain-to-source on resistance (Rdson). For example, a higher Rdson may result in an increased inductance of the high voltage device, in turn resulting in a lower switching speed and more energy loss during switching. Further, the reliability of high voltage devices may be affected by impact ionization generated hot carriers trapped at silicon and silicon oxide interface regions along the current path. Such hot carriers can generate defects in the high voltage device and cause linear drain current (Idlin) degradation.
Accordingly, it is desirable to provide an improved high voltage device with a higher switching speed and greater reliability.